The bill would require big spenders, including unions, corporations, and nonprofits, to disclose donations exceeding $10,000 to independent groups. Democrats contend such rules are needed since the Supreme Court, in its 2010 Citizens United decision, declared that corporations and unions have a constitutional right to spend freely on elections. The decision led to the rise of super PACs and nonprofit groups, which have been major players in national politics, especially the race for president.

“We’re not here seeking a limitation on spending; we ought to be, but we’re not,” Senator John Kerry, a Massachusetts Democrat, said in a floor speech before the vote. “We’re here simply to get the American people the right to know who’s giving the money, who’s paying these millions of dollars, in order to affect the debate in America — in most cases, I will tell you frankly, to distort the debate.”

His Massachusetts counterpart, Republican Scott Brown, called the legislation “a cynical ploy masquerading as reform” in restating his opposition. Brown voted against a previous version put to a vote in 2010.

“Rather than treat all sides equally as a true reform bill would, it contains special carve-outs for union bosses and other favored interest groups,” he said. - BOBBY CAINA CALVAN

Ayotte among GOP senators opposed to high seas treaty

WASHINGTON — A three-decade effort to persuade the United States to ratify a global treaty ruling the high seas has again encountered rough waters, with three more Republican senators saying they would oppose ratification.

That brings the number opposed to 34 senators, enough to prevent ratification of the Law of the Sea treaty. The Constitution requires two-thirds Senate approval of any treaty.

Support for the treaty has been widespread, with leaders from the military, State Department, and business community contending it would help protect the country’s security and economic interests across the oceans. Ratification has been a top goal of Senator John F. Kerry, chairman of the Senate Foreign Relations Committee.

Opponents, however, say the treaty would undermine US sovereignty. Republican senators Kelly Ayotte of New Hampshire and Rob Portman of Ohio announced on Monday they oppose ratification.

In a letter to the Senate majority leader, Harry Reid, a Democrat from Nevada, Ayotte, and Portman said the treaty was not in nation’s best interests. “The terms of the treaty are not only expansive, but illdefined,” the letter said.

A third Republican, Johnny Isakson of Georgia, had recently announced his opposition.

The United States is the only major power to not have signed the treaty, which was negotiated in 1982 and went into effect in 1994. Among other elements, the treaty established tribunals to adjudicate conflicts over territorial waters and other jurisdictional issues.

Supporters had included big-business groups such as the oil and gas industry, which wants to protect US interests in the increasingly navigable regions of the Arctic. - BOBBY CAINA CALVAN

Paul won’t be allowed to speak at GOP convention

WASHINGTON — Defeated Republican presidential candidate Ron Paul is asking discouraged supporters to bring a ‘‘positive tone’’ to a rally near the GOP convention in Tampa next month after he was denied a chance to speak to the delegates that will nominate Mitt Romney.

Paul told supporters in a video message on his campaign website that their approach would ‘‘very, very crucial to people wanting to listen’’ to the libertarian message that he had doggedly carried through stateby- state Republican primaries and nearly two dozen GOP presidential debates.

‘‘If the tone is positive, we’re more likely to have success,’’ Paul told supporters who have seen the veteran Texas congressman excluded from speaking at two GOP conventions in a row.

In order to qualify to speak to the delegates, a candidate needs the support of at least five state delegations at the convention. Paul had the support of four: Louisiana, Iowa, Maine, and Minnesota. Nebraska was the last state delegation to consider the issue and, over the weekend, decided to withhold its support, leaving him with one state short and no speaking slot. - HOUSTON CHRONICLE

Republican ad hits Obama, but with a gentler tone

WASHINGTON — The Republican National Committee is airing a television ad that says President Obama tried and failed to fix the economy, and that it is OK to make a change.

The ad is critical of Obama, but in milder terms than other commercials. Instead, it appears designed to persuade voters to back a new president even though Obama’s favorability ratings remain high. It does not mention Republican candidate Mitt Romney.

The ad says Obama took office with big plans to repair the economy, but the country now has an economic crisis with no end in sight. It concludes: ‘‘He tried. You tried. It’s OK to make a change.’’

The commercial is airing in Ohio, Virginia, Nevada, New Hampshire, North Carolina, Colorado, and Iowa at a cost of about $5 million. - ASSOCIATED PRESS

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